How To Insulate a Shed?

[Totally Scrambled]

Well it's more of a workshop really, measuring approx 10' x 13' internally with apex roof, 7' at the eaves and 8'6" to the apex. It is shiplapped on three sides and thick feather edged on the fourth side. It has power and light.
I have been thinking of insulating between the battens and rafters and putting plyboard over the top to insulate it and deaden the noises I occasionally make while inside it but it seems a minefield of conflicting advice.
Some say just slap insulation in the gaps and board, while others say you need breathable membranes, waterproof membranes, air gaps or not between each material, specific types of insulation to avoid mould, damp rot, dry rot, fungus etc.
Obviously I want it to insulate against cold/heat and to deaden noise and I don't want the stuff to soak up moisture and rot the structure from the middle outwards.
I'm hoping someone on here can help me out with clear, simple advice to get the job done without having to buy diamond encrusted materials that cost the earth.
I was leaning towards rockwool slabs which are good for temp control, accoustic baffling and are water resistant but then started to research the web and confused myself
Dom

[perchy]

What are you going to do in there?

Making the kids more comfy

[Steve the Gas]

I would use rockwool bats and board it, make sure there is general ventilation - should be fine....

[perchy]

I would use rockwool bats and board it, make sure there is general ventilation - should be fine....

Yes Steve I agree

[p.penn]

I would use the foil covered polystyrene insulating boards if I were you.

[perchy]

I would use the foil covered polystyrene insulating boards if I were you.

yes Helen I agree

[Sara]

Dom. When you become an expert in this would you mind insulating my work shop please?

[Totally Scrambled]

What are you going to do in there?

Making the kids more comfy

Blue jobs involving wood and loads of machinary making a racket.

I would use the foil covered polystyrene insulating boards if I were you.

Thank you for the suggestion Helen but that doesn't deaden the noise much and apparently polystyrene can react with the PVC sheathing on electrical wiring.

Dom. When you become an expert in this would you mind insulating my work shop please?

Sara you live in France and everyone knows foreign places never get cold so don't need insulation
Dom

[Totally Scrambled]

Steve,
So you don't reckon I'll need anything else other that the rockwool slabs and whatever I used to line the inside wall.
I was thinking of leaving a 1" gap between the slabs and outer wall/roof so that air could move around to stop moisture getting trapped and using exterior grade ply as the inside facing.
Dom

[perchy]

You're up to something, does Ali know

[foghornleghorn2]

Simplest way is to clad the inside of the walls and roof with glass-fibre wool, tacking a sheet of board onto the frame to hold the insulation between the board and cladding. Don't compress the wool because it's the air that actually does the insulation, so if you have a 32mm frame you get the best value from the insulation by using a 32mm matt of wool to fill the void between the board and cladding.

Thing is, if the shed wasn't lined with breather paper when it was built you'll get rain drive through the cladding. Without the insulation and boarding that's not too much of a problem because it just sits on the inside of the cladding and evaporates away, but now it'll just sit there and rot the shed.

So you really need to line the shed if it isn't already. Buy breathable lining membrane from the builder's merchants. Tack this all over the inside of the walls and ceiling before you sandwich the rock-wool. Trouble is, if the shed wasn't designed to be lined, water that does come through the cladding won't get into the insulation, but it will still hang around between the cladding and breather paper and cause trouble.

So the pukka job would actually be to stretch the breather paper over the frame (and if there isn't a frame on the ceiling you'll need to batten it) so there's a ventilated void between the cladding and the paper, then tack a batten onto the frame to the depth you want to insulate to. This also has the advantage that you can now apply a reasonable amount of insulation.

Small sheds need a greater thickness of insulation than big ones because the ratio of wall area to volume is greater for the small shed than it is for the big shed, and while the heat is held in the volume, it's lost from the wall area. So you could easily want 6" of insulation for a modest size shed. So for example, a 6' x 4' shed is now 5' x 3' inside, and probably not much more than 5' high.

And don't forget the floor. It doesn't loose as much heat as the ceiling, but it still looses quite a bit. And if the shed just has a regular shed door the whole door and frame will need upgrading to something draft-proof.

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Above text taken from a shed building website


http://www.shedblog.co.uk/sf-forum/just ... -question/

[Steve the Gas]

Nice one Foggers

To keep cost to a min - I would do it my way - but holding the bats back with praps a semi - permeable membrane.

[Totally Scrambled]

Foggy,
Cheers for that. The shed has a masonary wall about 2' from the rear shed wall and another building about 2' from one end wall and is under trees, so doesn't get much in the way of driving rain. The outside is painted so will that mean that water penetrating through the wood won't be a problem?

So the pukka job would actually be to stretch the breather paper over the frame (and if there isn't a frame on the ceiling you'll need to batten it) so there's a ventilated void between the cladding and the paper, then tack a batten onto the frame to the depth you want to insulate to. This also has the advantage that you can now apply a reasonable amount of insulation.

Do you mean put the paper over the faces of the battens on the inside, then add another layer of battens over the top and then insulate and board? One wall is made up of 4"x4" posts, could I tack a batten frame around each recess and put the breather paper over this then insulate and board?
Dom

[p.penn]

To keep cost to a min - I would do it my way - but holding the bats back with praps a semi - permeable membrane.

I didn't realise he had bats in his shed.

Dom, you may not even be allowed to insulate in case you kill them - your shed may even aquire listed building status.

[Steve the Gas]

I think it would be on the shed side with the bats behind the membrane...iyswim